Twists and turns: a tale of two shikimate-pathway enzymes. (1st June 2003)

• Record Type: Journal Article
• Authors: Brown, K.A.; Carpenter, E.P.; Watson, K.A.; Coggins, J.R.; Hawkins, A.R.; Koch, M.H.J.; Svergun, D.I.
• Is Part Of: Biochemical Society transactions. Volume 31:Number 3(2003)
• Page Start: 543
• Page End: 547
• Publication Date: 2003-06-01
• Subjects: crystal structure -- dehydroquinate synthase -- enolpyruvylshikmate phosphate synthase -- shikimate pathway -- small-angle X-ray scattering; Biochemistry -- Congresses; 572
• DOI: 10.1042/bst0310543
• Languages: English
• ISSNs: 0300-5127

Abstract

Abstract : We are studying two enzymes from the shikimate pathway, dehydroquinate synthase (DHQS) and 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Both enzymes have been the subject of numerous studies to elucidate their reaction mechanisms. Crystal structures of DHQS and EPSPS in the presence and absence of substrates, cofactors and/or inhibitors are now available. These structures reveal movements of domains, rearrangements of loops and changes in side-chain positions necessary for the formation of a catalytically competent active site. The potential for using complementary small-angle X-ray scattering (SAXS) studies to confirm the presence of these structural differences in solution has also been explored. Comparative analysis of crystal structures, in the presence and absence of ligands, has revealed structural features critical for substrate-binding and catalysis. We have also analysed these structures by generating GRID energy maps to detect favourable binding sites. The combination of X-ray crystallography, SAXS and computational techniques provides an enhanced analysis of structural features important for the function of these complex enzymes.